Black blue

How Black blue behaves on a wall

RAL Colors publishes a light reflectance value of 4.6 for this shade. At LRV 4.6 this is a deep shade: it returns under an eighth of the light that reaches it, so a room painted in it leans on lamps rather than daylight. Over a pale base it usually takes an extra coat before the colour stops looking patchy. For trim that reads as a clear edge rather than a smudge, aim about 30 LRV points away — roughly LRV 35 and up. Its blue channel runs ahead of its red, so it reads cool and will sharpen next to steel, glass and grey stone. Order by the code, not the name, and put a test patch on the wall before you commit — a screen cannot show you how this shade behaves in your own light.